Corneal Edema

What Is a Corneal Edema?

Corneal edema refers to the swelling of the cornea — the clear, dome-shaped outer surface of the eye that helps you see clearly. This condition is caused by a buildup of fluid in the cornea. When left untreated, corneal edema can lead to cloudy vision.

Symptoms of a Corneal Edema

Buildup of fluid in the cornea causes vision to blur and become clouded. These effects are at their worst when first waking up in the morning, but will fade throughout the day as the cornea dries from the eyes being open.

Other symptoms of corneal edema may include:

• Rings or halos around light sources
• Pain in the eye
• The feeling of something stuck in the eye

Causes of a Corneal Edema

The cornea is made up of layers of tissue that help focus light on the back of the eye to produce clear images. Along the inner surface of the cornea is a layer of cells called the endothelium. Its job is to pump out any fluid that collects inside the eye. Damage to this layer results in excess fluid building up, clouding up the cornea and affecting vision.

Fuchs’ dystrophy is a disease that affects the endothelium, which can cause corneal edema.

Endotheliitis, an immune response of herpes, is another cause of inflammation of the endothelium.

Certain drugs can also increase the risk of developing corneal edema, including benzalkonium chloride and chlorhexidine.

Corneal Edema Treatment Options

Mild cases of corneal edema may not need any treatment. If there is swelling, your ophthalmologist may recommend saline eye drops.

If swelling becomes severe enough to cause significant vision issues, surgery may be required to either replace the cornea with a corneal transplant, or DSEK surgery, which replaces just the endothelial layer.